Hello everyone, I recently connected an electric fan with an adjustable thermostat into my 71 maverick. I made some adjustments to the thermostat to nail down the desired temperature in which I wanted the fan to turn on/off. This thermostat has a probe that is inserted and clamped down through the upper radiator hose and works great. Right now, I have the positive fused lead connected to the positive terminal on the battery to get the full 12V. I read that it should be connected to an ignition switch lead which I would rather it be. So, this is where I need your help. Previously, I connected it to the alternator but realized the voltage dropped to 5V I believe leaving the fan to struggle. I have a 6A MSD ignition. Where is the best place to connect this 12V to to allow it to activate via a ignition switch and power down immediately after the ignition is turned off? It bothers me a small bit to hear the fan going. Please be specific where to connect, thanks everyone.
Check the discussion on this thread http://mmb.maverick.to/showthread.php?t=80027 for an auxilary fuse block. It gives you the option of switched or constant on and prepares you for the next project. Personally, I like having the elect fan with constant on power. It runs for several seconds 2-3 times after I shut it off but am experiencing no problems with battery. Running a little after shut off cools the engine and under hood. Others HAVE had the battery run down. Guess it depends on your set up.
Same here, I've probably had mine like this for the last 10 years and never drained the battery. Now I have a 2-speed Taurus fan, runs on HIGH with the key on and LOW with the key off, so very minimal current draw with the engine not running.
I like mine running after shut down also. But the feed to power the fan controller being connected to 12v batt. is too much draw. Its always awake monitoring the temp and will drain the Batt in about 4 days. So it has to go. I have a relay box set up to eliminate all this now. I ran a relay for Ignition fed items like the fan controller. I use an Ign feed from in the car just to power the control side of the relay. This way the old factory wiring isnt running my add ons on the load circuit. I use the same idea for the horn and head lamps with a Batt feed instead of Ign feed on the control side of the relay. Now I have easily accessible, reliable 12v batt feeds as well as Ign feeds under the hood. I would suggest this for a rad fan contoller, MSD etc. Then you know you have a nice fresh 12v supply to the load circuit of the relay from the batt. This is really simple to do and takes the load off the old wiring. A fan controller ignition feed is low load anyhow but this relay could be used to run more than one item. EG. MSD. Terminal 30--- From 12v batt supply fused. Terminal 87--- To Ign feed for fan controller/Ign feed for MSD etc. Termianl 86--- From Ign feed from in car Terminal 85--- Ground Note: This is to power the Igniton feed for the controller that turns the controller on and off. Not the heavy 12v feed to the fan.
http://www.therangerstation.com/tech_library/diagrams/relays1.jpg Heres a simple little pic. I love relays.
Darren, something is different in mine because when we returned from 2+ weeks away, with the Maverick sitting in the garage for that time, the battery showed no sign of weakness. Some day I'll check the current draw for my fan controller. What do you think would be an acceptable TOTAL current draw with ignition off? I know there are specs on that for modern cars but don't know what the spec would be. IIRC, the instructions on my fan controller gave the option of switched or constant on power connection.
40-50 milli amps is a good all round spec for ignition off draw. MY controller is above that so I had to change it to Ign feed. My controller form Carquest gave the option as well but it didnt work out.
The Flex-a-lite 31149 Temp Control Module is the only thing I have that would draw current with the key off. With pos battery cable disconnected, I get 70 ma between the battery cable and battery post. If the car was going to sit for months, I'd have the Battery Tender on it.
My controller is not connected to the ign. I have it on a toggle sw on the dash. The sw is to the battery 12v, fused thru firewall , frm there to a relays that op fan and in car aux fuse block. In other words , forget to turn on the sw and u will overheat. Not a problem, as long as I am the only one driving the car. I don't have any draw as long the sw is off.
